The invention relates to a fall arrest safety apparatus with blocking on a rope, comprising:                a rigid body provided with a trunking for housing the rope,        a securing system designed to swivel between a closed position to collaborate with the rope by blocking the latter at the bottom of the trunking in case of a fall, and an open position releasing access to the trunking for fitting or removal of the rope,        and a control device to move said securing system from the closed position to the open position, and vice-versa.        